Rubber spring shackle



Oct. 13, 1931 c.A R. sHom' 1,827,268

' RUBBER SPRING SHACKLE l v Original Filed Feb. 4, 197:21'l

gmc/nto@ y -67145 'g5/f -I Original' application illed February 4, 41927, Serial No. 165,887. Divided and this application ledlJuly 2.3,

' 1,931. Serial Patented Oct.` 13,' 1.931

UNITED STATES .PATENT OFFICE CHARLES R. SHORT, OF DETROIT, HICHIGAIL'AS'SIGNOR To GENERAL MOT-ORS RE- SEARCH CORPORATION, OE DETROIT, MICHIGAN, A CORPORATION or DELAWARE RUBBER SPRING SHACHLE This invention .relates to the construction of rubber spring shackles and the novelty resides in eliminating an rubbing action or friction between the rub er and metal parts, characteristic of prior constructions. IThis rubbing action isdeleterious to the rubber and wears it away in a short time and-when applied to vehicle springs this worn away portion will allow the vehicle lbody to sway from side to side producing shimmying,'i. e., al Wing the wheels to move bodily relative to thU body of the car. Or when turning, the wheels will take their proper course around the curve but the body will tend to go straight ahead and the play Aallowed "by the worn shacklel will cause a sway of the body relative to the wheels.

. A common trouble with rubber or rubber fabric shackles isthe lateral flexibility which affects steering and induces low speed shimmying. Free movement must be provided to accommodate `the lengthening of Spring but all 'movement at right angles to the length of the spring should be avoided. It is proposed to conine' the' rubber in a pocket from which itis prevented' fromilowing, for in this manner it-.will resist deflection in onedirection while permitting free movement in the desired direction.

My invention further is concerned with an improved method of making rubber bearings, which 'consists inl extruding the rubber in tube form of required dimensions as to outbar of the chassis, 2 the sprin bracket se-` side diameter and size of hole, cutting the tubeto required lengths, placing the sections so made upon-a hollow arbor or tube, which u may be cylindrical of polygonal and 'straight or formed with transverse corrugations throughout all or part of its length. `Atubu lar member is then -placed over the rubber ring section and contracted by swaging or pressing to the required diameter,- the tube at the same time being elongated. The rubber ring will be deformed and 'placedmnder tension causing it to practically lill the annulus between the inner core member and the outer or shell member. A' small space is allowed between the rubber and the, ends of thevshells to prevent any rubber-metal rubbing action.

T he outer or shell member may be further foimed by rolling or pressing to form corrugationsat rightangles to its axis. The pur-y pose of so forming the inner core member and the outer shell being to limit the possible movement ofthe bearing along its axis while' permitting it to rotate more lor less freely according to the composition of rubber used and the degree of compression to which it is A subjected by contracting the outer shell.

The rubberportion may also be distorted and placed in tension by expanding the innerV Figure 2 is a section on line 2-2, Figure v1,

with parts shown in section for purposes of clearer illustration.

Figures '3 and 4 show dili'erent stages of -the construction oi my improved joint. Figures 5 and 6 show a modiied form in dierent stages of construction;

Figures 7 and 8 show a second modification in two 'different stages of construction, Figure-8 showing the struct-ure after the swaging has taken place.

Figures A9 and 10 Show athird modification' in two different stages of construction. w

Referring toFigure 1, 1 designates the side cured to the chassis 1, 3 the usua leaf spring and'l 4. the shackle arms.'y 5 designates the shackle bolts which extent through the eye 6 ofthe bracket or the eye 7 of the spring 3.

Surrounding the bolt 5 is an inner shell 8 l which is enclosed in an outer shell 9 closely fitting within the eye 6 of the bracket.

the Shells as shown at S. The shells 8 and v9 at their ends are in close contact with the shackle arms4 andare thereby incapable, of

an transverse movement.`

Be-v tween the shells 8 and 9 is a yieldable tubular filler member 10 which may be of any suitable material, but is preferably of rubr ber, and is slightly spaced from the ends of novel .joint is better shown. The tube of rubber 10 is assembled over the shell 9 and the shorter shell 9 in turn placed over the rubber c linder 10. By a swaging action the cylin er 9 is deformed or contracted and forced closerto the cylinder 8, causing the yielding material 10`to be compressed and spread and substantially fill in the annulus betweenthe two shells, as shown in Figure 4. The completed joint member is shown in Figure 4 in which the shells 8 and 9 arethe same length and in this form is assembled within the shackle as shown in Figure 2.

In the modification in Figures 5 and 6, the inner shell 8 is the same as-in previous figures, while 9 indicates an outer shell, the equivalent of the shell 9 in Figure 2. 11 denotes two wedge members or bushings placed in either end of the shell 9', and 12 is av tube of resilient material, preferably rubber'. The inner shell 8 has a ring 13 triangular in cross section surrounding its c tral portion. The bushings 11 are tapered at their inner ends .asshown at14 and by forcing these bushings towardv each other the rubber 12 is'compressed and caused to spread and fill in the space between the wedges, the Ishell 8 and its ring 13 as is shown in Figure 6. In the final form of the'joint member the rubber is under compression.

In the modification shown in Figures 7 and 8, the inner shell 8 is corrugated or ribbed transversely of its length as shown at 15, while the outershell 9a is swaged onto the rubber 10 and the lower shell and later formed with the protuberance or corrugations 16 which conform to the eorrugations 15 ofthe shell 8. The shell 9a has small inturned flanges 17 at 'its ends for strengthening purposes and to assist in retaining the rubber, but these flanges arel unessential and may be omitted. To prevent friction between the rubber and flanges 17 a small space S is allowed therebetween. In the joint member in its finalform as shown in Figure 8 the rubber 1'0 is under compression and closely fills the eorrugations and the space between the shells 8 and 9a.

In the modification shown in Figures 9 and 10, the inner shell 8 has transverse corrugations similar to Ithe corrugations shown in the inner shell in Figures 7 and 8 and` the outer shell 9 surrounds the rubber tube 12 as to the vehicle. 'Ihis is articularly true of a species wherein the bus ings are corrugated, the corrugations tending to prevent any transverse movement of the parts.

This application is a division of my prior application Serial No. 165,887, filed February 4, 1927. l

I claim:

1. A joint comprising a bolt and arms,`a shell surrounding said bolt, a second shell surroundin the first shell, the ends of both shells abutting said arms, a resilient material under compression arranged between said shells but out of contact with said arms, and an eye member surrounding said second shell.

2. In a joint, a bolt and arms, a cylindrical shell surroundingjsaid bolt and having portions thereof pressed from its surface, a second shell surrounding said first shell and having portions thereof pressed from its surface, a resilient material under compression arranged between said shells but ont of con roundingl said second shell.

8. In a spring shackle joint, a frame, a bracket secured to the frame, an eye on the bracket, a spring having an eye, a pair of shackle arms at the 'wo sides of the bracket and spring eyes, and a joint member in each eye, said member comprising anY inner bolt receiving shell and an outer shell closely received within the eye, protuberances on both shells, and an elastic medium under compression between said shells.v

4. A resilient joint, comprising a cylinder Ytact with said arms, and an eye member surforming a journal, a socket of larger diameter at the central portion than atthe ends, and a. tube made of resilient material firmly coinpressed between the central cylinder and the socket". Y

5. A joint comprising an inner corrugated shell, an outer cylindrical shell of greater length than the inner shell and an elastic medium between said shells.

In testimony whereof I affix my signature.

CHARLES R. SHORT.

in the previous forms and is swaged on to the inner shell'causing the rubber 12 to be compressed and spread and substantially fill the nodes between the corrugations and the space between the shells 8 and 9 as is .shown in Figure 10.

With the structures as shown in the fig;

ures described the arrangement is such as will permit a rotational, a longitudinal or up and down motion withinthe limits al` lowed by the compressed rubber but will resist any transverse movement with reference 

